Bike Reviews

The original Photon won our Editors' Choice Dream Road prize in 2010. We lauded its 747-gram frame, sprightly climbing ability, and snappy, responsive ride quality. Guru revised the Photon in 2013, expanding it to a three-bike line that includes the SL reviewed here, the super-stiff Photon R (for race), and the gossamer Photon HL (hyperlight).

The SL (superlight) is the most direct descendant of the original Photon, says Nicolas McCrae, composites engineer for Guru. "We wanted to show what we've learned in the past few years," he told me. The new model has rounded main tubes that are similar to the original's--but now they flare at the junctions to increase surface area; the larger joint allows the front triangle to better resist twisting stresses.

The Photon SL has the same ethereal climbing qualities as the original; its handling was quick and even more crisp than in previous iterations, thanks to the stiffer frame. The rigid Reynolds Assault SLG wheels would be excellent for racing, but they made the bike ride a bit more harshly than I liked. Switching to Shimano C24 hoops restored the smoothly damped, almost polished ride I remembered from the earlier model.

Guru's frame sizes and geometry differ among the SL, HL, and R, making direct comparisons difficult. Generally, the SL has a slightly taller bar height and shorter reach, which put me in a more upright position. If you race and prize stiffness, the R is a better choice; the HL obviously has the lightest frame. But the Photon SL hits a wide sweet spot, a performance bike with a gorgeous ride.

FABRIQUE AU QUEBEC
Guru builds its Photon frames at its factory in Quebec, which allows the company to do rapid prototyping of new ideas or designs that would take months on the usual Asian-built program. North American manufacturing also offers Guru access to military-grade carbon that isn't sold in China.—Joe Lindsey